Manufacture of new azo dyes



Patented 7 May r 6, 1930 UNITED STATES PATENT OFFICE JAMES BADDILEY, PERCY CHORLEY, AND RAINALD BRIGHTMAN, OE MANCHESTER, I

ENGLAND, ASSIGNORS TO BRITISH DYESTUFFS CORPORATION LIMITED, OF MAN- CHESTER, ENGLAND, A CORPORATION OF GREAT BRITAIN j,

MANUFACTURE or NEw Azo DYES No Drawing. Application filed March 2, 1927, Serial No. 172,199, and in Great Britain June 25, 1826.

Renewed September a, 1929.

' We have found that if 2-amino- 8 naphthol- 6-sulphonic acid is mixed in aqueous solution with an equimolecular proportion of a suitable aniline or naphthylamine derivative,

that is to say, a primary aromatic amino body, other than an aminonaphthol or an aminonaphthol sulphonic acid, and the mixture is treated with phosgene in the presence of 10 sodium acetate or alkali'es, there is formed an unsymmetrical urea having theconstitution' represented by the general formula on n NC-I I--R HOaS to these specific examples. The primary aromatic amino bodies which may be used in our process are represented by the general formula 5 H N- -R wherein R -represents a non-hydroxylated aryl group or residue.

The unsymmetrical ureas can be coupled with any of the known diazo compounds to give anew range of azo dyestuffs. According to the nature ofv the diazo compound chosen, these dyestufl's find application for dyeing regenerated cellulose silks, or for dyeing cotton. Mono or disazo dyes may be produced by coupling these unsymmetrical ureas with a diazotized aryl mono amine or a diazotized amino azo compound or a tetrazotized diamino diaryl compound. The monoazo dyes in the form of the free acid aryl group or residue, R represents a divalent may be represented bythe probable general formula wherein R represents a non-hydroxylated aryl. group or residue and R represents a monovalent aryl residue. The .disazo dyes are of two types. One-type may be represented in the form of the free acid by the probable general formula wherein R represents a non-hydroxylated aryl residue and R represents a monovalent aryl'residue or group. The other type of disazo dye may be represented in the form of the free acid by the probable general formula OCH; p.00

wherein R represents a non-hydroxylated aryl group or residue. In the present application we do not claim the new ureas, but the new class of dyestuffs obtained from them.

The following examples illustrate the invention, Without limiting it, the parts being by weight Ewample I Congo red paper throughout, is well stirred thylurea-G 6-disulphonic 'acid, which: sepaand phosgene is passed in until no further rates first, the sodium salt of 8-h.ydroxy-2:2- reaction is obtained with sodium nitrite. The dinaphthylurea-(i: 6-disu1'phoni'c acid is prei m pp y y y yci itated by the addition of common salt.

- 6-sulpho-2-naphthylurea separates and This compound in the form of the free acid 70 tered off. This unsymmetrical urea co1nh th b bl f l pound has in the form' of the free acid, the 4 probable formula en i Example [I 5 which is well "agitated and maintained faintin form of h free @cidhas the P b H088 Example IV 319 parts of dehydrothio-p-toluidine"sulso 239 parts of 2-amino-8-naphthol-63-sulphonic acid are diazotized' with 69 parts of phonic acid, dissolved in 2000 parts of water sodium nitrite and 300 parts of 36 per cent and ao'pms of sodium hydroxide, are mixed hydrochloricacid in the usual way and the ao'w'ith an aqueous solution of 245 parts of the suspension of diazo compoundformed is run 85 sodium salt of -naphthylaminc4-sulphonicinto a cold, well stirred, aqueous solution of .acid. The mixture is well agitated and phos- 437 parts of the sodium s lt f t midogene'is passed into it, sufficient sodium hyh l-8--h d -6- 1 h 2; phth 1m- (ll-oxide being added to maintain an alkaline w d 500 parts f di ga m The reaction throughout 1 the reaction mixture is maintained alkaline and stirred 90 complete thefiodlum l h y until coupling is complete, when it is heated cal )I 8 c y 'q y 2 p y up and the dycstufl isolated by the addition 'dlsulphomc mild, 1S sellamted yof common salt. Thedyestufi' obtained dyes dttlon F P salt Thls unsymmetl'lcill viscose silk in Bordeaux-red, shades.- It is dmaphthylurea 1n the 'form of the free: acid a dark brown powd'r-giving a bluisbred has the Probable formula lution. in water and in aqueous alkali, the colour changing to brown on acidification; H H the dye dissolves in concentrated sulphuric a acid with a deep crimsoncolour, chan in N i N Solm c on dilution with waterfirst to brown anc l mo Ho's then to red. The dyestuff 1n the form of the y l free acid has the probable formula Y Ema lam" Ifin place'of deh dro-thio-p-toluidine sulh""'d277 tf b 239 parts of- 2-amino-8naphthol-6-sul omclacl l i r P' P i phonic acidfdissolved in 2000 parts of water l fl gi i 9 with 3 r and 106 parts of sodium carbonate, are mixed palts o mm 2 m e usua Y I with an aqueous solution of 245 parts of the coupled alkaline sqlutlon. there IS sodium salt of ,B-naphthylamine-6-sulphonic lal'ly .obfiamed EQY EIfi whlch dyescotton acid phosgene is Passed into the mixture a claret shade, 'Ihe disazo dye so obtalned 4 1y alkaline throughout by the 1 addition of formula- 120 v 4 sodium hydroxide. I After filtering ofl' the so- Likewise other diazotizable compounds dium salt of the more insoluble 2: 2'-d'n1ap h maylbe substituted for the dehydrothiotolut I OaH ' When aminoazo compounds are diazotized and coupled disazo dyes are obtained. For

i This disazo dye in the form of instance the aminoazo compound formed by i gum-mm 80:11

The substitution of. 122 parts of dianisidine for the p-chlorani1ine in' the above exam 1e "(Example V) results in the formation 0 a dyestufi' which gives violet shades on cotton.

This .disazo dyestufl' in the form of the free acid has the probable formula Emmpze 'Vl 127.5 parts of para-chloraniline are diazocoupling diazotized' metanilic acid with tizedwith 69 parts of sodium nitrite and 250 alpha-naphthylamine is used, there isspro- 'Fparts of 36 per cent hydrochloric acid in the ducedqa product 'Which dyes cotton blue. usual way." The diazo solution is run into thefree acid has the probable formula OH H wherein R5 represents the divalent residue from the alpha-naphthylamine and R representsvthe monovalent sulphonated phenyl residue from the metanilic acid. The exact position of the, coupling isnot known.

V l 2' dinaphthylurea A. 6 -disulphonic acid obtained as described in Example II; aredissolved in Water and 250 parts of sodium. carbonate. -To this solution, cooled-and well agitated is added the dia'z 'o solution obtained 1 by treating127 .5 parts of para-chloraniline with 69rparts of sodium nitrite in the usual way. The mixture is maintained alkaline and stirred until coupling is complete, when it is heated up and the dyestuif isolated by the addition of common salt. The dyestuif obtained dyes viscose silk a red shade. This monoazddyestuif in the form of the free acid has the probable formula."

a cold Well-stirred solution of 488 parts of p 8 hydroxy 2 2' dinaPhthyIurea-S 6-disulphonic acid and 370 parts "of sodium carbonate.-- The mixture is maintained alkaline r the addition of common salt. .The dyestuflf obtained dyes viscose silk a red shade. This monoazo dyestuff inthe form of the free acid has the probable formula In the structural formula'given the probable formula is indicated, as the, exact posi- LA process of manufacture of new dyestuffs consisting in combining a diazo com Y s5" RAINALD BRIGHTMAN.

pound with a new urea represented by the general formula:

5 p a NH.COLNH.R.

in which R represents a phenyl or .naphthyl m residue, said residue being nonhydroxylated.

2. A process of manufacture of a new dyestufi consisting in coupling diazotized dehydrothio-p-toluidine sulphonic acidin alkaline solution with p-acetamidophenyl-8-hydroxy-G-sulpho-2-naphthyl-urea.

3. The new dyestuff obtained by combining a diazo compound with a new urea represented by the general formula:

in which R represents a phenyl or naphthyl residue, said residue being nonhydroxylated,

which dyes regenerated cellulose silks and cotton in level shades.

. 4. The new dyestuii obtained by coupling. diazotized dehydrothio-p-toluidine sulphon- Rfi icacid in alkaline solution with p-acetamidophenyl 8 hydoxy-G-sulpho-2 naphthyl-urea, p which has the form of a dark brown powder,

giving a bluish-red solution in water and in a-queous alkali, the colour changing to brown on acidification; and which dissolves in concentrated sulphuric acid with a deep crimson colour, ch nging on dilution with water first to brown and thento red. v

5. In the manufacture of new monoazo dye- 40 stuffs, the process which comprises combining a new urea having the general formula:

on o H H n ilz-o-i r-Oz r-o ona with a diazo compound. -i 6.. As new monoazo dyestufis, the coinm, pounds obtained by coupling a diazo compound with a new urea represented by the general formula nms the said dyestuffs dyeing regenerated cellulose silks and cotton in level shades. In testimony whereof we aflix our signatures. j

' JAMES' BADDILEY.

PERCY- CHORLEY. 

